


Back to the Start

by Amuly



Category: Marvel 616, The Avengers (Marvel) - All Media Types
Genre: Alternate Canon, Alternate Universe - Canon Divergence, Avengers Vol. 5 (2013), Fluff and Angst, M/M, SteveTonyFest, Time Travel, Vomiting, background T'Challa/Namor
Language: English
Status: Completed
Published: 2014-06-25
Updated: 2014-06-25
Packaged: 2018-02-04 20:30:33
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 8,048
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1792207
Author URL: https://archiveofourown.org/users/Amuly/pseuds/Amuly
Summary: <blockquote class="userstuff">
              <p>Sometimes the cause comes after the effect. Sometimes the beginning is after the end. Sometimes honeymoons follow divorces and marriages come after both. Steve and Tony may be doing everything out of order and backwards, but given the way the universe is unfolding, can you really blame them?</p><p>Set immediately after Avengers Vol 5 Issue 30. Obviously will vary wildly from canon for every issue after.</p>
            </blockquote>





	Back to the Start

**Author's Note:**

> Written for [shaliara](http://www.shaliara.tumblr.com) for the Steve Tony Fest gift exchange. Hope you like ^.^

The screen flickered in front of Tony, technology strained to its limits. He waited, eyes burning, nose throbbing, knuckles stinging. His eyes darted back and forth across the screen, hand pressed to his chin as he waited, and watched. His computer would manage it. He had designed the program, or at least, reverse-engineered it. One rogue planet wasn't the only thing that granddaughter of his had left with him. She also left her energy signature, and the algorithm that propelled her backwards through time. And snapped her back again.

That's what this was—that was something in what Clint had said, in the future. Rubber bands pulled back and back and back until they snapped forward again, back into their own time. Steve being pulled further and further away from him through time. Maybe he'd overshoot, on the snap back. Maybe he'd end up back in the forties where he could settle down and be happy. Maybe Tony's luck would bring him that.

The laugh was dry in Tony's throat, more of a cough. His luck wasn't that good. And his masochistic streak wanted Steve to come back to him. Even if he came hurtling back with the force of ten thousand years screaming behind him.

That's what his algorithm was telling him, at least. Ten thousand years. Tony sure hoped the Earth existed ten thousand years into this future. That Steve and Natasha and Clint didn't end up asphyxiating when the time gem plopped them down into the space where earth was. Or dying from radiation poisoning on a dead earth. Or a million other scenarios Tony could think of in time travel gone wrong.

The screen flickered again, and Tony's mouth tightened. It would work. It had to work. Steve was forty-two years away from him when Tony left him. He needed to find how many more years away he was now. The screen flickered. Tony's hand dug into his chin.

 _There_! Tony started forward, hands reaching for the screen. Four hundred and twenty-two years. Dear God. What could the world be like, four _centuries_ away? Just about as different as today was from _sixteen_ hundred years ago, given the exponential growth of human expansion. Was it post-singularity? No, not according to his granddaughter. She was from a thousand years in the future, and it wasn't post-singularity.

Okay, so he had found them. Now what? Tony cracked his knuckles. A plan. He needed a plan.

“If you guys are getting pulled away from me...” Tony mused. “How do I reach _you_?”

On the screen in front of him, Steve was staring around the futuristic city, jaw tight and back straight. His eyes were scanning the horizon for something. Tony's eyes narrowed.

“ _I_ know how to reach you.”

* * *

Steve jerked, head spinning. Flashes of forgotten meetings and half-truths bashed against his mind, pounding against the backs of his eyes. He took a stumbling step forward, lurching against Natasha.

“Steve! Steve, are you okay?”

Arm shooting out, Steve pushed Natasha off him. He shook his head like a wet dog, or a bull trying to shake a rider. The visions buffeted against his mind, then cleared. He took a tremulous breath.

“Steve.”

“I'm fine,” he told Natasha, one hand still out. “Just give me a second. I'm fine.”

“We don't exactly have a second, Steve,” Natasha observed. “Clint's gone—both Clints. We've jumped forward who knows how much further in time, and- _Steve_.”

Steve jerked upright, head clear of visions. He didn't know what _that_ was, but-

He blinked at the sight before him. He didn't know what _that_ was, either.

“ _Steve Rogers_.”

An Iron Man floated in front of them, in the air above a technologically advanced New York City. Steve glanced over at his team—diminished already. Clint said he didn't make it to the next jump. Where did he go, then? Was he alive? Was he back with Tony? Or was he dead unless they fixed things? Tony would have some idea.

Steve clenched his jaw and nodded at the Iron Man. “Yes. That's me.”

“ _Message from Tony Stark. Circa twenty fourteen_.”

“Tony?” Steve started forward, then stopped. He was perched on the back of a sky cycle that Natasha was piloting. He didn't exactly have a lot of maneuverability afforded to him at the moment.

“ _Message from Tony Stark. Circa twenty fourteen_.”

Steve reached up to pluck at his helmet wings in frustration, then remembered he didn't have them. He sighed and settled for rubbing a hand over the crown of his helmet. Okay. Tony was sending him a secret message from the past. What would the password be?

“This is Captain America,” Steve tried.

“ _Security confirmation needed_.”

Steve thought for a moment. “ _Steve_ ,” Natasha warned. Every bit of proximity equipment they had was beeping. The Iron Man suit wasn't the only thing interested in them. He had to figure this out quick.

Tony would have made this after he went back. He would have set this up and sent it to them... or had it lie in wait, right. Waiting for the year he knew they'd get sent to, somehow. Or waiting for them to show up after the last year they were in, waiting for their DNA or Thor's magical signature to show up, something. What password would Tony have given his Iron Man? Something he knew Steve would know. Illuminati? Incursions? Something _only_ Steve would know.

“Radiohead.”

He got a few odd looks from his teammates, Steve could see it out of the corner of his eye. Steve rubbed at his helmet again. He hoped he knew Tony—and Tony's sentimental streak—as well as he thought.

The Iron Man armor hovered threateningly in the air. Steve held his breath. “ _Confirmed_. _Follow_.”

Steve looked at his team, waiting for the signal from him. They were already down Clint, gone who knows where. Maybe snapped back through time. If he had been and old man in the last jump, then he survived. He must have. But it meant Steve might lose a person with every jump. Now he had Natasha, Hyperion, Thor, and Starbrand with him. A powerful team, but not a large one. Not necessarily large enough to fight off an ambush that four hundred years in the future could throw at him.

But the confirmation code had been “Radiohead”. It had to be from Tony.

But how much could he really trust Tony, right now?

He had no other choice. Proximity klaxons were blaring from everyone's equipment. They had to get out of the air before they got themselves captured by who knows what defensive system. Steve nodded to the rest of the team and tapped Natasha's shoulder. “We're going with the Iron Man.”

She nodded and revved up the sky cycle. The Iron Man blasted through the city, trusting them to follow. Steve only caught glimpses of their surroundings: flying cars and jets all around them, floating buildings, more skyscrapers than New York had ever had in his day. It looked like a bright, shinning future. Steve wondered how much Tony would get a kick out of all this tech. Then he wondered what they had sacrificed to get to this point. What compromises they made. What worlds they had erased.

The Iron Man led them to some skyscraper, down to the ground floor and below. They found themselves in a basement, maintained but far from the technological beauty of the rest of the city. The doors closed behind them and Steve held his shield at the ready.

No attack was mounted against them; no trap lay in wait. The Iron Man unit settled itself against a dusty wall, into a spot that looked like it had occupied for years and years. Once it was in position, a lens in its helmet flared to life. A holograph flickered in front of it, before solidifying. A full-sized recording of Tony Stark came to life a foot from Steve's face. He took two steps back.

“ _If you're listening to this message, it means I calculated correctly. We don't have much time, and I have a lot of info to dump on you. So please, just listen and don't_ argue _with me for once_.”

Steve grunted. The rest of the team was looking at him askance. He could _listen_. Tony was being an asshole. Four hundred years in the future, and Tony was _still_ being an asshole.

The Iron Man didn't care about his petulant grunt and kept playing the recording. “ _I'm not sure exactly what's going on. But I'm pretty sure it's all connected. The incursions, the infinity gauntlet, the time gem disappearing and reappearing. Black Swan, the war against the builders, the destruction of the superflow... Steve, it's a Monet. And you're my big picture guy. I need you to be my eyes and ears, and I need you to get enough distance and perspective on this thing to figure out what we need to do.”_

The image of Tony shifted, staring at his hands for a long moment. While the pause lengthened, Steve took in Tony's disheveled appearance. The Stark Resilient lab scrubs, the broken nose, the swollen jaw. His eyes were bloodshot, one even brighter red with broken capillaries. Steve's heart clenched before it burned. _Tony_ had done this. This was _Tony's_ mess. This was _Tony's_ burden of guilt. _Not. His._

Tony on the screen continued again, finally looking up from his hands. “ _I think the answers to save our present are in our future. And I need you to find them for me, Steve. I don't know exactly what you need to look for. But I can lay you out some guidelines. Some rules. Maybe it'll help._

“ _Number one._ ” Holographic Tony held up a single finger. “ _Being back here allowed me the chance to get a read on you guys. I've calculated that you're going to make two more jumps, each time by a factor of ten. This time you're four hundred twenty-two years in the future. Next jump is going to put you four thousand years in the future. I'll have another drone waiting there for you. Problem: your last jump before you snap back to the moment you left will put you forty-odd thousand years into the future. I don't have that kind of tech, Steve. No one has that kind of tech. I'm not going to be able to reach you, then. Anything I could build short of lasering my face into a mountainside will be long gone, decayed into atoms and entropy by then. You'll be on your own._ ”

Thor twirled his hammer idly, one shoulder propped against Hyperion's. “We have faced worse situations with less warriors at our sides. This should not pose a problem.”

Steve nodded once, though he wasn't convinced himself. Would the world even _be_ here forty _thousand_ years into the future? Would it be liveable? They were lucky to have survived this far.

“ _Number two: You'll come back, in the end. You're like a rubber band being pulled further and further away. Once you hit that last jump, you'll snap back to the moment you left. I think. Pretty sure. Number three: I've managed a rough calculation as to how long you'll be in each time. Clint said it'll increase, everything I'm looking at says it's going by factors of ten. First time was ten minutes. I think this time'll be a hundred. After that a thousand, then ten thousand. That's a hair under a week_.”

“You're not the only one who can divide,” Steve grumbled at the hologram.

“ _And I know you can do that math in your head, too. Just saying it for the sake of the class._ ” The Tony on the screen smirked, holographic smile wavering and flickering in the unsteady light the Iron Man projected. Steve clenched his jaw and cast his eyes away.

At his side, Natasha leaned in to stage-whisper: “You have to admit, he's always had your number.”

“ _Other than that, all I can give you are guesses. I'd say try to find descendents of Richards, of me, of Banner, of T'Challa, Pym... anyone else you can think of who might have a technical handle on the situation. Ask about the incursions. Gather as much information you can. Did they solve it? How? Is this the only universe left, or did others survive? It's pretty much cheating, asking the future for the answers to the past, but fuck it: you guys are getting hurtled through the timestream, might as well make the best of it._ ”

“That's your best idea?” Steve growled. “ _Ask_ how we solved it?”

“ _It's worth a shot_ ,” Tony said, shrugging. Steve blinked at the holograph.

“ _Oh, yeah: I can look into the future and see how you're going to respond to this and then modify the recording to respond to it. Some of it's guesswork since as soon as I change something in the recording it changes how you respond, but I kind of got a handle on it._ ”

Steve shook his head.

“Cheater.”

“ _Cheater_.”

Steve's head snapped up, smile tugging against his best efforts at the corners of his mouth. The holographic Tony was looking at him with the same expression, except with tears in his eyes. Steve cast his eyes down. There were no tears in his.

“ _I've wasted enough of your time, now. You've got about sixty minutes left in this time. Make the most of it. I'll be watching, best as I can. The mirror is... it's screwy. The further away you get the muddier it is. I'm trying, but I can't... there's only so much I can do. Figure it out, Steve. Avengers. You might be our only shot. And Steve,_ ”

Steve lifted his head to look the holograph in the eyes. Tony stared him down, through the four hundred years that separated them.

“ _You were the one that refused to consider the utilitarian option. Now's your chance. Find a better way. Otherwise we'll be left with no other choice if we want to survive._ ”

“You're trying to _goad_ me into saving the world,” Steve pointed out.

“ _Has that ever failed_?” The holograph flickered, then steadied. Tony winked. “ _Save the day. Prove me wrong. I'll be waiting for you guys when you get back. And I'll let you take me in to whatever authority you want, if that's what you feel is best_.”

The holograph flickered again, and this time went out. Steve was left staring at a blank wall, and a deactivated Iron Man robot. Steve resisted the urge to put his fist through it. The only good it would do would be to break his hand. Probably.

“Friend Steve?” Thor prompted him.

Steve sighed and tugged off his helmet so he could run one hand through his hair. The cool air of the basement was a relief on his skin. “Alright. We do as Tony says. We've got an hour. Who can find descendents of all the scientists we know?”

* * *

Back in the year twenty fourteen, Tony watched as Steve listened to his message four hundred years in waiting. He'd watched this conversation a dozen times, modifying his own recording over and over again, adjusting it as Steve responded to the new recording, then going back and recording it again, then watching it again.

They found Reed's kids. Or his kids' kids' kids. Descendents of the Richards, twin girls with the sharp eyes of their ancestor Sue and the sharp smiles of their ancestor Johnny, coupled with an intelligence to outshine Reed's by a long shot. Blonde and brunette, one for each of their great great great etcetera grandparents. Tony grinned as he watched them, wondering if Reed would be proud or jealous. Probably proud. They were part of him, after all.

Tony watched them, he watched the energy spikes, he watched his own algorithms flicker and dance and adjust themselves on his screen. But mostly he watched Steve, watching the twins. Watching the world around him. Taking it on, observing every nuance that he could. Sharp eyes of an expert tactician ever on the alert for information... or danger.

As such, it shouldn't have surprised Tony when Steve noticed it first. Shouldn't have, but it did.

“Stop. Go back.” Steve wasn't even looking at the group when he said it—his eyes were trained on a mid-sized airship, speeding away from them a hundred yards up. But he lowered his chin and looked at the twins after he spoke, leaving no question as who his word were addressed to.

The blonde twin looked to her sister, then to Steve. “Which part?” she asked.

“'Those don't exist in out history,'” the brunette tried, repeating the gist of what she had been explaining to the group. “These incursion events. Maybe it was a different timeline. With infinite worlds-”

“No. You said it,” Steve interrupted her. “Hasn't happened in your _history_. These incursion events, it was a multiverse-wide chain reaction. No universe could have not heard of them.” He hesitated, glancing over his shoulder. Looking for something. Looking for someone.

Four hundred years in the past, Tony's heart tried to pound its way out of his chest. Steve was looking for _him_.

“Keep going,” Tony murmured at his screen. The glow from it was the only thing illuminating his sad little quarters in T'Challa's necropolis. Tony leaned forward into the cold warmth of the screen. “You've got this.”

After another moment looking for something that wasn't there, Steve turned back to the twins. “It hasn't happened yet. Whatever started off the chain reaction—because it had to be something, right? Aristotle had something to say about that. Unstarted starter, or...”

“An unmoved mover,” the blonde twin put in.

Steve snapped his fingers at her. “Right. An unmoved mover. Everything has a cause except that. So the cause of the incursions, of the multiverse-destroying chain reaction, it's out there, it just must have not _happened_ yet.” Steve rubbed at his jaw, thinking. “Right?”

Brunette twin shrugged one shoulder. “Wouldn't be unheard of. And if these incursions really do effect _every_ universe, as you believe, then for ours to have no history of them limits the possibilities. It could be that the first action in the chain hasn't happened yet.”

Blonde twin hummed, eyes narrowed. “Or it could mean that whatever solution there is to the problem eliminates its existence entirely from the timestream.”

Steve chewed his lip. “Shoot. I guess so.” He hesitated, one hand drifting up to fiddle with helmet wings that weren't there. Tony made a note to have a word with Jan about this costume redesign. Chic or not, Winghead without his head wings was just wrong.

“Well, we'll just have to pursue both options,” Steve said after a moment. “Thank you ladies for your time. I think ours is almost up, unfortunately-”

“No, wait!” Tony scrambled at the screen. “I think you're right. Damn it, Steve. Of all the times for you _not_ to go with your gut...”

Tony snapped off the feed. Okay, okay. It was okay. He had time. All the time in the world. He just needed to make something that would last four thousand years, and be able to find Steve when the time came. Four thousand years. No problem.

He'd get to Steve. That asshole couldn't escape the long arm of Tony Stark, no matter how far into the future he went.

* * *

The world spun around Steve less, this time. Which was odd: his intuition said it should be worse, the further away he was pulled from his original timeline. Tony had likened it to a rubber band being pulled back until it snapped into its original place. Shouldn't the increased tension make things worse?

Unless he had been right in his theory, and the time gem was pulling them forward to where they should be. To the start of it all, at the end.

The city around them was... organic. Not natural, not like the forest had come back to reclaim Manhattan. It was artificial, man made, but... organic. It was such a departure from what he knew that it took Steve a couple minutes of looking before he realized what was wrong.

“Where's Starbrand?” he asked the group.

Hyperion and Thor both looked around for a moment before settling on nearly identical shrugs. Natasha was messing with some equipment on her sky cycle. “It's the same readings as Hawkeye,” she observed. She looked up at Steve. “Clint was alive and... well enough, in the future. And he knew he didn't make it any further in the jumps. Some of us are just snapping back sooner than others, I'd guess.”

Steve worried at his helmet with one hand. He dropped it with a nod. “Nothing we can do about it, now. Only thing to do is keep moving forward. This is the third jump, so that means we must be about four thousand years out, if Tony's estimates are right.”

“One thousand minutes in this time,” Natasha added.

“Sixteen hours forty-five. No, forty,” Steve corrected himself quickly. He glanced down at his wriststrap. The whole damn thing was busted—figured. He'd just have to go off his internal clock. Lucky it was pretty accurate. He clapped his hands together. “Alright, we got a double-shift to figure out what we can from this time period. Any thoughts?”

“ _Steve. Rogers_.”

Steve sighed. An Iron Man was stepping across the ground beneath them, speakers pointed high. Steve twirled a finger in the air, motioning for his team to go to ground. They did, Hyperion and Thor landing on either side of the robot, Natasha planting the skycycle directly in front of it. Steve hopped off, feet sinking into the slightly mossy ground. He glanced down for a moment, taking that second to assess his surroundings. It wasn't undergrowth—not natural, at least. The moss was actually pavers of some sort, forming a smooth, if somewhat springy floor to walk on.

“Steve Rogers here. Got something for me, Iron Man?”

The robot in front of them creaked worryingly. Steve examined it with a critical eye. He didn't understand tech the way Tony did, but he knew this Iron Man was technologically inferior to most things Tony built. It looked closer to the original armor that got Tony out of the cave in Afghanistan than any of the suits he battled in regularly. Was that because he didn't have a lot of time? Was this thrown together under some sort of ticking clock? Or did it have something to do with them being four thousand years in the future? Maybe old-school was the only thing Tony could build that would survive this long.

“ _Steve. Rogers._ ” Steve could actually hear the gears clicking inside the great metal man as it spoke. He frowned. It sounded and looked like it might fall apart any minute. Hopefully it got through its message before then. “ _Massage from Tony Stark: You have right. Trust your gut. The start if the incursions mast be in the future. Stop it._ ”

The machine man slowed down, gears clicking tiredly. Steve stepped towards it, hands reaching, like there was anything he could do. After a long, pathetic whirring, the Iron Man started up again. “ _Black Swum said Rabum Alal was the beginning if the end. Go to the end to find the beginning. Rabum Alal is_ -” the gears slowed, creaked, then stopped. From the way the Iron Man rattled and spat rust, Steve knew that was the last life he had in him.

“Steve?” Natasha prompted him.

Taking off his helmet, Steve wiped at his hair a half dozen times. Riddles within riddles. Why couldn't Tony just spit the message out?! He _knew_ he had a limited amount of time to say whatever it was he needed to say. Why didn't he just _say_ it?!

“Maybe we can find someone who can fix it. Get us the rest of the message. We have sixteen hours in this jump. Should give us plenty of time.” Steve scratched at his ear, thinking. “Well, at least I understood the part where I was right...” Steve mumbled.

* * *

Tony threw his helmet across the lab, nearly braining T'Challa as he walked in. He dodged the helmet, easily, raising an elegant eyebrow at Tony as it clattered to a stop. As T'Challa stepped into the room— _his_ room, because everything in Wakanda was his—Namor appeared in the doorway behind him. Tony growled and turned away from them. Two were attached at the hip these days. Tony wouldn't be surprised to find out the expression was literal for them, as of late.

“Need some help?”

Tony sneered at T'Challa. “Unless you have an idea how to get someone a message forty thousand years from now, I think I'm good, thanks.”

“The long arm of your ego doesn't extend that far?” Namor laughed.

Tony jabbed a finger at him. “If you're not going to be useful, how about you shut up your pointy eyebrows, asshole!”

Perhaps the ridiculousness of the insult shocked him into silence, because Namor's mouth snapped shut.

T'Challa seemed to be taking the problem seriously, at least. “No materials would last, but if you create something self-replicating, that could replicate the instructions to build replacements of itself as well as the message you want to send...”

“Four thousand years out it was already breaking down,” Tony explained impatiently. “I already did it! Four thousand years there were transcription errors, mechanical faults, and the damn thing didn't even relay the whole message. It's like I already told Cap: short of lasering my face into a mountain-”

Tony stopped. His fingers pressed together, then opened.

“Oh. There's an idea.”

Namor looked sidelong at T'Challa. “Should I be the one to stop him, or leave it to you?”

* * *

Steve was getting the hang of this time jumping, he thought. As much as you could get the hang of something like this. He hopped onto the back of Natasha's sky cycle as the world around them settled, eyes searching for whatever it was he was supposed to see.

Nothing. The city was peaceful, an organism teaming with life, throbbing with the pulse of humanity. Steve looked back at his team. Thor was gone. “Natasha? Thor.”

Natasha's fingers were already skimming over her controls. “Same readings as before. This is the last jump, so...”

“So we should be seeing them soon,” Steve finished for her. He looked out on the vibrant city. “One way or the other.”

Hyperion floated beside them, expression faintly worried. “Is there a plan of action, Captain?”

“Tony tried to tell me what we were here to stop,” Steve thought aloud. This “Rabum Alal. Something about him, something he does, we have to stop. The beginning-”

“Steve.” The instruments on Natasha's sky cycle were going crazy. Natasha swept red hair out of her face as she worked, trying to get a handle on her equipment. “There's something happening. It's a signal beacon, set on our channel. It's...” She looked up, expression as startled as Steve had ever seen it. Which was the most worrying thing thus far on this strange voyage. “It's coming from the moon.”

Steve looked up, the pale white orb visible to the east of the city. He shrugged. “Whelp. Better see what that's about.”

Natasha's sky cycle was S.H.I.E.L.D. issue, which meant with the push of a button—and a little help with momentum courtesy Hyperion—Steve and Natasha were blasting off to the moon, Hyperion following close next to them.

“Picking up anything?” Steve asked as they sped their way above the cratered surface. There were glowing lights spattered over the moon, stations and colonies and who knew what else. Steve had once listened to Tony present a scientific proposal to Congress about something called “Helium Three,” which could be mined on the moon for nuclear fusion power plants. They had asked him about the feasibility of making a fusion bomb with the stuff, and Tony had shut down, taken all his research and budget proposals back home with him. Steve wondered if maybe some of those clusters of lights were Tony's peaceful vision come to reality.

“it's the other side,” Natasha announced. She snorted. “Dark side of the moon. If this is from Stark, I'm going to kick him in the shins when we get back.”

Steve bit back a retort about how Tony had been beat up enough recently. Bringing it up would indict himself for his own, perhaps hasty, reaction. Not that it was unjustified.

Steve's knuckles cracked as they clenched in his leather gloves.

“There!” Natasha pointed ahead of them, at...

“What is it?” Hyperion asked.

“An impact site?” Natasha mused.

Steve's jaw tightened. No. He knew what this was. “It's a message.”

“It's writing,” Hyperion observed.

“On the _moon_.”

Steve stood up on the back of the sky cycle, hair brushing the top of the protective bubble that had come up around the vehicle. It _was_ writing. Giant, thousand-foot long letters formed a message on the face of the moon itself. Steve's mouth dropped open as Natasha flew them into position. Tony had said he wouldn't be able to send them a message that would last for forty thousand years short of lasering his face into the mountain.

So he lasered his message into the face of the moon. Of course he did.

As they flew further, the words slowly took shape between craters and mountains that peppered the moon. Steve mouthed the words as they became clear:

RABUM ALAL IS THE MULE.

STOP HIM BEFORE THE FIRST EVENT.

HYPERION: HOLD-

There was an impact over the last letters. The site of a detonation, or meteorite hit. Steve stared down at the moon with his mouth hanging open, throat working futilely.

“Hold _what_?” Steve shouted. “Hold on? Hold back? Hold the phone? _Damn it, Tony_! Just when I needed you to _work_ , to do something _right_ -”

Natasha grabbed Steve's shoulders, pulling him back. He had started towards the edge of the sky cycle without realizing it.

“Steve. _Think_. The message was for you. You're the only one who will know what he's trying to say.”

“Why couldn't he just _say_ _it_ ,” Steve fumed. Because it was _always_ like this, wasn't it? With the mind wipes, with the battle for Tony's armor, with the SHRA, with _everything_. Tony had to have his schemes within schemes, plans within plans, and just expect everyone to listen to him, to trust him, because he was Tony. Fucking. Stark.

“You and Tony share a bond,” Hyperion pointed out. “Thor has called it the bond of shield brothers. Forged in battle and hard-won. You speak a language between yourselves that is foreign to all others.”

“Radiohead,” Natasha reminded him. She smiled tightly and squeezed his shoulder. “I didn't even know that, and I'm the Black Widow.”

Steve took one deep breath, then another. Natasha and Hyperion were right. For all their ups and downs—and maybe _because_ of all their ups and downs—Tony knew Steve better than just about anyone on earth. For him to risk something this big, this far into the future, meant he _needed_ Steve to understand this. And Tony had a lifetime to plan it. Steve was meant to see this; Steve was meant to understand it.

“Is it a drug mule?” Natasha asked. “Or a pack mule? Is he transporting something? Especially stubborn?”

“No.” An idea flashed in the back of Steve's mind. A drawing. “Classic” science fiction, written decades after his death, collected and bound in anthologies that needed illustrations. Illustrations done by an old-timey sci-fi nut that sometimes dabbled in Captain America comic books. Illustrations Tony had the original copies of, purchased at auction and signed and kept with all his collectible Captain America merchandise. All his Steve mementos and keepsakes. Tony's keepsakes of Steve's life.

“It's _the_ Mule,” Steve breathed. “It's _Asimov_.”

“Isaac Asimov? The science fiction writer?” Natasha's eyes flickered over to Hyperion's, who shrugged.

“I illustrated it!” Steve exclaimed. “The _Foundation_ novels. When they were repackaged, some anniversary edition. I illustrated the Mule. He was-” Steve's throat clenched, eyes burning hot with the realization.

Forty thousand years in the past, Tony shouted at his crackling screens: “ _A black swan event_.”

Forty thousand years in the future, Steve whispered: “ _A black swan event_.”

Steve turned to Natasha and Hyperion. "We have to find him. Rabum Alal. We have to make sure he doesn't destroy earth. The _first_ Earth, the one that started it all, that brought two universes into collision for the first time.”

Tony's screens were filled with snowy static, Steve's face barely discernible amidst forty thousand years of interference. He howled as he slapped at his monitor, trying to catch the smallest hint of how things were going. If there was anything he could do to help.

“Hype – zzz – find – zzz – zzz – zzz – Earth – zzz – zzz – Alal – zzz –”

Forty thousand years in the future, Hyperion was at the nexus of two universes.

“You have to hold!” Steve shouted.

Forty thousand years in the past, Steve's voice shouting the word “ _Hold_!” echoed through Tony's dark quarters in the city of the dead.

Tony grabbed his monitor between his hands, fists clenched as if in prayer. “ _Hold_!” he shouted at Hyperion, forty thousand years into the future.

“ _Hold_!” Steve shouted again, shield between his hands, fists clenched in prayer.

* * *

The snap back was worse than any of the jumps forward. Steve and Natasha threw up, hands on their knees and knees on the floor. Hyperion collapsed against Thor's shoulder. In the back of his mind Steve took note of Thor's presence, and that he seemed well. Clint and Kevin, too. They had snapped back as predicted. Good.

“Steve, are you-”

Steve shook his head, eyes burning and mouth tasting like vomit. A water bottle pressed into his hand, and he took it gratefully. Next to him, Natasha was gurgling the water and spitting it out. Steve followed suit.

Only then did he look up to see Tony's worried face look down at him, eyes bloodshot and bruised, cheeks gaunt. Gosh, he looked worse than before, on the holograph a hundred years into the future. How much time had passed here? How much time had passed for Tony?

Steve held a hand up.

* * *

Tony flinched, half-expecting another sock to his jaw. Not like he didn't deserve it. But Steve was just asking for a hand up. Tony sighed and took it, hands wrapping around each other's forearms tightly as he pulled Steve upright. Steve's smile was exhausted, but genuine.

“You're back.”

Steve sighed, shaking his head ruefully. He didn't let go of Tony's arm when Tony did his; instead, he pulled Tony closer, tugging him into a hug. Tony tensed, then relaxed, breathing out his tension over Steve's shoulder.

“I'm back.” Steve's chest rumbled against Tony's as he whispered the words against his neck.

“You did it,” Tony breathed. He couldn't believe it. He watched it happen, mostly. He'd felt the effects as the cause forward in time moved backwards to them. But he could hardly believe it.

Steve laughed, face blotchy red from stress and happiness. “We did it!” he told Tony, shaking him by the shoulders. The exuberance dropped from his expression, turning quietly serious from one moment to the next. “ _We_ did it. Tony, you...”

Tony shook his head. “You had it. Hyperion had it. You guys hardly needed me, pestering you through time like the nagging aunt that wouldn't die.”

Steve leaned in and kissed Tony. Tony was so shocked he stopped talking. Maybe that was the point.

When Steve pulled back his face was blotchy red again. He wiped at his mouth shamefully. “Sorry, sorry. I just threw up, I shouldn't have-”

“Don't worry about it,” Tony mumbled.

“I just... I'm back,” Steve breathed. And his voice, his stupid fucking voice wasn't the Captain America voice. It was the kid-from-Brooklyn voice, the voice of wonderment and happiness and love for life that made Tony first fall for him. It was that voice that pulled Tony in. It was that voice that pushed him away.

Nudging himself a step back, Tony cast his eyes down and laughed hollowly. “Thought maybe you wouldn't come. After all, last time you went to the future you decided to stay.”

When Steve didn't say anything, Tony risked a glance up. And oh boy, that was a mistake, it was a _trick_ , a damned dirty trick on Steve's part. Because he was _looking_ at Tony, that serious, sad look that he _only_ ever used with Tony. “I stayed in the future with _you_ ,” Steve told him, words clipped, voice hard. “I came back to the past for _you_.”

Tony rubbed his jaw, trying to play it off like a joke. Defuse and deflect. Avoid Steve's emotional gravitas like it was Mjolnir around DUM-E's circuitry. “Needed to finish what you started?” he joked, tapping meaningfully at his jaw. “How about the other side, this time? You were bad enough, but add in a cybernetic Hawkeye and my face is about at its limits.”

“You finished what you started.” Steve's voice was... Tony didn't even know. He couldn't read Steve's expression, and wasn't _that_ terrifying.

“What?”

Steve stepped forward, hand lifted, and Tony forced himself not to flinch for the second time in so many minutes. Steve's hand came down on Tony's shoulder, squeezing it tightly. “I'm so proud of you,” he told Tony. “You finished what you started. And you didn't have to compromise. You stayed a good man. You stayed yourself.”

Tony laughed harshly. Steve's hand was too heavy on his shoulder. “Why don't you ask Steve Rogers how good of a guy I am? I feel like he'd have a different opinion...”

“Steve Rogers can be an asshole,” Steve grumbled. This time _he_ dropped his eyes, much to Tony's surprise. And delight. “Steve Rogers can be... a... a jerk who gets too mule-headed and then...” Steve blew air between his teeth in frustration. His cheeks reddened. “Too mule-headed, and then gets angry when people go behind his back... Not that you _should_ have, you _should have_ talked to me. You stayed moral, Tony, you found the right answer, and if you had just promised me from the _start_ -”

Gingerly Tony lifted Steve's big hand from his shoulder with his thumb and forefinger. “Promised you what? That I wouldn't make the unconscionable decision? Because I would have, Steve.” His gut churned as he thought about world 4,290,001. “I might have. Given the opportunity. Did you want me to promise you I'd find the impossible solution? I'm a futurist, Steve, but I couldn't have foreseen this. It was a black swan event.”

Steve frowned. “Maybe you're the futurist, but I know _you_ , Tony. I knew from the start that the only way out of this was something... different. Lateral. Something you hadn't thought of yet, but you _could_ , if you didn't focus all your time on weapons manufacturing...”

“Are we really having this argument,” Tony moaned, staring at the ceiling. “I just brought you back through time from the year forty-four _thousand_ one hundred and fourteen _and simultaneously_ figured out how to save _every universe that exists to infinity_ and we're having this argument. You know what, Steve? Save your pride for someone else. I've had about as much as I can take before I choke on it.”

“Tony, no, wait-” Steve grabbed onto Tony's shoulder, tugging him back when he turned away. Tony shot him a glare, shrugging his shoulder roughly. Steve dropped his hand in response, stepping back as a peace offering. “Tony. I don't want to have this argument, either.”

“Then maybe dial back the righteousness about eleven notches,” Tony snapped, twisting his hand like he was turning a dial.

“I was trying to tell you how proud I am of you!” Steve huffed, exasperated.

“Well I don't want to _hear it_!” Tony shot back.

Steve stuck his hands out imploringly. “What do you want to hear then, Tony? What do you want from me?”

“I want you to _stick with me_ , Steve! I want you to shove your righteousness for two seconds and _trust me_. I want you to be at my side all the time, not just when it's easy.”

“I love you,” Steve told Tony, like a promise.

Tony's eyes cut away, welling up with tears. “Not enough.”

In one motion Steve stepped forward and wrapped his arms around Tony, pulling him into his chest. Tony didn't have to suppress a flinch this time. He didn't want to flinch. “Gosh darn it, Tony. I came back to you. I came back _for_ you. I will always come back to you.”

“Yeah, well.” Tony's hands curled at his sides, wanting to lift them, to hug Steve back, but not willing to give him the satisfaction. “It's not enough.”

Pulling back, Steve held tight to Tony's shoulders and shook him, just lightly. Just enough to make his point. “Then let me do more. Earth's saved. Like you said: _every_ Earth is saved, in _every_ universe. That's a pretty big win. You deserve some time off.”

“You kicking me off the team?” Tony snorted and rolled his eyes. “Thought you already did that. Before your little jaunt through the future.”

“I'm kicking us _both_ off,” Steve corrected him, not rising to the bait. “Until future notice, Carol can be in charge. You and me? We're out of New York, for as long as we need to be. For as long as it takes for me to love you enough. Because you deserve it, Tony.”

“What are you, sacrificing yourself for the greater good, as my consolation prize?”

“No. You're mine.”

A thrill went through Tony, at the way Steve said that. A guilty, shameful, never-going-to-let-Steve-know-about _that_ thrill.

“You should work on that possessive streak of yours, Rogers.”

“Where do you want to go?” Steve asked, ignoring him. “I've never been to Florida. I hear that's the place to go after a big win.”

“You're just going to ignore everything I say,” Tony wondered, scanning Steve's expression.

Steve grinned at him. “You know, maybe it was traveling forty thousand years into the future, but suddenly I'm finding it a heck of a lot easier to ignore your self-destructive jibes.”

“Hasn't updated the way you speak, though,” Tony pointed out. Then, after hesitating for a moment, he said: “Florida is okay. We could do better, though. Hawaii or Fiji or the Cayman Islands...”

Steve shrugged. “I'm not exactly one for vacations. You tell me where we're going and I'm there.”

“Is this a date?” Tony asked.

Steve snorted. “Date? It's a little late for that, isn't it?”

Tony laughed. “Honeymoon, then?”

“We're not married,” Steve pointed out.

“We're not? How the hell have we managed to get divorced three times, then?”

Turning around, Steve brought Tony with him, tucked under his arm. Tony let himself be led out of the artificial light of his lab. “Do I even want to know what you're counting?”

“When I took you down trying to get my armors back from the government...” Tony started.

Steve shook him, arm still wrapped tight over his shoulders. “I don't want to count. Let's focus on this, first. Worry about the divorces later.”

* * *

Tony's sunglasses were pushed down to the edge of his nose as his blue eyes squinted over at Steve. “Are you sunburned?”

Steve smiled and closed his eyes behind his own sunglasses. “I can't get sunburned. Serum heals it.”

“No, you can't get _tan_ , because the serum heals it,” Tony pointed out. “You were sunburned at the end of the day yesterday, you know. You just... healed overnight. Now you're getting sunburned again.”

Steve shrugged one shoulder. “Doesn't hurt.”

“Should you be wearing sunscreen? Can you get skin cancer?”

Steve laughed and opened his eyes again, tilting his head to one side so he could smile at Tony. “Is this an excuse to rub suntan lotion on my back?”

Tony was chewing at his lower lip. “Normally you'd be spot on but actually I'm just concerned. You're _Irish_. Do you know how many Irish guys I know who get cancer dug out of their face every other week?”

Steve wrinkled up his nose at the mental image. “How many Irish men or women do you know whose cells are infused with a super-soldier serum?” he asked.

“Still.”

“Are _you_ wearing suntan lotion?” Steve asked him.

Tony snorted. “Uh, have you ever compared my skin tone to yours? Come on. Put some on your nose at least. The Statue of Liberty would shed bitter tears if you had to mar up your pretty face by cutting off the tip of your nose.”

Steve rolled his eyes but finally held out his hand. “Fine, pass it here.”

Tony threw the lotion too hard at him, but Steve still caught it easily. He stuck his tongue out at Tony, who stuck his tongue out back at him. Just as he was dabbing a glob of the white goop onto his face, a brown-haired boy and blonde-haired girl ran up to them, feet jumping back and forth on the hot sand.

“Um... Um... Um...” the boy tried.

The girl, who was older than him by a few years, stepped forward: “ _AreyouCaptainAmericanadIronMan_ ?!” she asked in a rush. “ _Canwetakeapicture_?!”

Smiling over at Tony, Steve clicked the lotion shut. “Sure.” As they both stood up, Tony stepped over to Steve and reached for his face. Steve smiled as Tony smoothed the suntan lotion into his skin, rubbing in all the white goop until it disappeared. “Better?” Steve asked.

“I'm doing your neck and shoulders after this,” Tony warned him. “You look like a tomato. A buff, Irish tomato.”

Tony plucked the cell phone from the girl's hands while Steve squatted down next to the little boy. “Hey, buddy. What's your name?”

The boy stared at Steve with the biggest, brownest eyes he'd ever seen. He didn't say a word.

The girl was busy explaining her phone to Tony. “ _AndyouhavetopressthepictureinthemiddletomakesureyougetitofcusedIwanttogetlikefivepicturesbecausemymomscrapbooksandweneedtogetabunchofpicturesincasetheycomeoutbad_ -”

Steve smiled some more at the little boy. “Wanna make muscle arms with me? Like this:” Steve brought one arm up to his shoulder, flexing his bicep. “Can you do that?”

Silently, big eyes never leaving Steve's face, the little boy brought his arm up and flexed it like Steve's. Steve smiled big at him. “That's great! Just like that. We'll do it together.”

Tony ended up making a silly face with the little girl for two pictures, then pretending to punch each other for another couple pictures, while Steve lead the boy through a couple muscle-flexing poses. When Tony handed the camera back to the little girl, she threw herself against his waist, wrapping him up in a tight hug. The boy stared at Steve until Steve held his hand up for a high five. Then the boy stared at him some more, until Steve picked his hand up and high-fived it to his own hand. The boy's mouth fell open, eyes growing impossibly wider.

When they left, Steve found himself being manhandled onto his stomach so Tony could lotion his back. Steve rolled his eyes but let him.

“You just made that kid's life,” Tony pointed out, laughter in his tone.

Cheek pillowed against his arms, Steve smiled faintly. “You, too. You were good with her.”

“I'm great with kids. Don't know why anyone would think otherwise,” Tony replied smugly.

After a beat, Steve suggested: “Well. You've got descendents in the future. Me, too.”

Tony's hands paused on his back, and for a second Steve worried that maybe he went too far, too fast. But then Tony was leaning down against his back, lips brushing against his ear. “Let's get through the honeymoon, first. Then we can worry about getting married and raising a litter.”

Rolling over, Steve grinned up at Tony, glare of the sun partially blocked by his head and mop of brown hair. “That's all out of order,” he pointed out.

Tony snorted. “When have we ever cared about chronology?” Then he leaned down and kissed Steve, and Steve brought his arms up to wrap around Tony as he kissed him back.

 


End file.
